[Results of two-year experimental trials on apple scab control in Veneto [Malus pumila Mill.]]

apples chemical control date de traitement enfermedades de las plantas epoca di trattamento fecha de tratamiento field experimentation insecticidas insecticide insecticides insetticidi lutte chimique maladie des plantes malattie delle piante malus pumila manzana mele plant diseases pomme sintomi symptome symptoms treatment date veneto venturia inaequalis